Method and apparatus for determining transmit power

ABSTRACT

A method and an apparatus for determining transmission power are disclosed. A gain factor of an E-DPDCH in a compressed mode is determined according to the number of E-DPDCHs used for initial transmission of data; and the transmission power of the E-DPDCH is determined according to the gain factor of the E-DPDCH in compressed mode. As the gain factor of E-DPDCH in compressed mode is determined according to the number of the E-DPDCHs for initial transmission of data, the gain factor of the E-DPDCH in compressed mode can be determined accurately, and thus the transmit power of the E-DPDCH can be determined accurately according to the gain factor of the E-DPDCH. Therefore, the waste of transmit power of the E-DPDCH is reduced, and thus the system capacity is improved.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/090,874, filed Apr. 20, 2011, which is a continuation ofInternational Application No. PCT/CN2009/074784, filed Nov. 4, 2009,which claims priority to Chinese Patent Application No. 200810172290.2,filed Nov. 4, 2008, all of which are hereby incorporated by reference intheir entireties.

This application is related to U.S. patent application Ser. No.13/100,516, filed May 4, 2011, and U.S. patent application Ser. No.13/250,073, filed Sep. 30, 2011, both of which are also incorporatedherein by reference in their entireties.

FIELD OF THE INVENTION

The present invention relates to communications technologies, and inparticular, to a method and an apparatus for determining transmit power.

BACKGROUND OF THE INVENTION

In a Wideband Code Division Multiple Access (WCDMA) system, the transmitpower required by an Enhanced Dedicated Channel Dedicated Physical DataChannel (E-DPDCH) can be obtained according to an E-DPDCH gain factor.The E-DPDCH gain factor may be calculated by an extrapolation formulausing one reference E-DCH Transport Format Combination (E-TFC). Theextrapolation formula is as follows:

$\begin{matrix}{\beta_{{ed},i,{harq}} = {\beta_{{ed},{ref}}\sqrt{\frac{L_{e,{ref}}}{L_{e,i}}}{\sqrt{\frac{K_{e,i}}{K_{e,{ref}}}} \cdot 10^{(\frac{\Delta \; {harq}}{20})}}}} & (1)\end{matrix}$

In the formula above, β_(ed,ref) denotes the E-DPDCH gain factor of thereference E-TFC; L_(e,ref) denotes the number of E-DPDCH used for thereference E-TFC; L_(e,i) denotes the number of E-DPDCH used for the i:thE-TFC (that is, the i:th E-TFC is corresponding to the E-DPDCH whoseE-DPDCH gain factor is currently to be obtained); if a spreading factorof E-DPDCH is 2, L_(e,i) and L_(e,ref) denote the number of channelsassuming a spreading factor of E-DPDCH is 4; K_(e,ref) denotes thetransport block size of the reference E-TFC; K_(e,i) denotes thetransport block size of the i:th E-TFC; and Δ_(harq) denotes an offsetof a Hybrid Automatic Repeat Request (HARQ), and is specified by theupper layer. Table 1 lists the values of Δ_(harq).

TABLE 1 Δharq Signal Value Δharq Power Offset (dB) 6 6 5 5 4 4 3 3 2 2 11 0 0

After the uplink 16 Quadrature Amplitude Modulation (16QAM) mode isintroduced into the WCDMA system, the uplink service rate increases to11.52 Mbps. With the increase of the service rate, a formula is putforward for calculating the E-DPDCH gain factor under high rateservices. This formula uses two reference E-TFCs, and is called aninterpolation formula. The interpolation formula is as follows:

$\beta_{{ed},i,{harq}} = {\sqrt{\frac{L_{e,{ref},1}}{L_{e,i}}} \cdot \sqrt{\left( {{\left( \frac{{\frac{L_{e,{ref},2}}{L_{e,{ref},1}}\beta_{{ed},{ref},2}^{2}} - \beta_{{ed},{ref},1}^{2}}{K_{e,{ref},2} - K_{e,{ref},1}} \right)\left( {K_{e,i} - K_{e,{ref},1}} \right)} + \beta_{{ed},{ref},1}^{2}} \right)} \cdot 10^{(\frac{\Delta \; {harq}}{20})}}$

In the formula above, β_(ed,i,harq) denotes the E-DPDCH gain factor;L_(e,i) denotes the number of E-DPDCH in non-compressed mode;β_(ed,ref,1) and β_(ed,ref,2) denote the E-DPDCH gain factors of thefirst and second reference E-TFCs respectively; L_(e,ref,1) andL_(e,ref,2) denote the number of E-DPDCHs used for the first and secondreference E-TFCs; if the spreading factor of E-DPDCH is 2, L_(e,ref,1)and L_(e,ref,2) denote the number of channels assuming the spreadingfactor of E-DPDCH is 4; K_(e,ref,1) and K_(e,ref,2) denote the transportblock sizes of the first and second reference E-TFCs; K_(e,i) denotesthe transport block size of the i:th E-TFC; and Δ_(harq) denotes theoffset of the HARQ, and is specified by the upper layer.

In the prior art, if the Transmission Time Interval (TTI) is 10 ms inthe compressed mode, the calculation of the E-DPDCH gain factor comes intwo scenarios: the current frame is a compressed frame, and the currentframe is a normal frame.

At least the following problems are found in the prior art:

in the prior art The E-DPDCH gain factor calculated out in compressedmode does not reflect the transmit power required by the E-DPDCHaccurately, and the transmit power required by the E-DPDCH which isdetermined according to the E-DPDCH gain factor is not accurate either.Consequently, part of the transmit power of E-DPDCH is wasted andtherefore the system capacity is reduced.

SUMMARY OF THE INVENTION

The embodiments of the present invention provide a method and anapparatus for determining transmit power so as to determine the transmitpower of E-DPDCH accurately and improve the system capacity.

To fulfill the foregoing objectives, a method for determining a transmitpower is provided in an embodiment of the present invention. The methodincludes:

determining the E-DPDCH gain factor in compressed mode according to thenumber of E-DPDCH required for initial transmission of data; and

determining transmit power of E-DPDCH according to the E-DPDCH gainfactor in compressed mode.

Further, an apparatus for determining a transmit power is provided in anembodiment of the present invention. The apparatus includes:

a gain factor determining module, configured to determine an E-DPDCHgain factor in compressed mode according to the number of E-DPDCHrequired for initial transmission of data; and

a power determining module, configured to determine transmit power ofE-DPDCH according to the E-DPDCH gain factor determined by the gaindetermining module.

Further still, a base station is provided in an embodiment of thepresent invention, and the base station includes the foregoing apparatusfor determining a transmit power.

Further still, a terminal is provided in an embodiment of the presentinvention, and the terminal includes the foregoing apparatus fordetermining a transmit power.

Compared with the prior art, the present invention brings at least thefollowing benefits: The E-DPDCH gain factor in compressed mode isdetermined according to the number of E-DPDCH required for initialtransmission of data, and therefore, the E-DPDCH gain factor incompressed mode is determined accurately, the transmit power of E-DPDCHis determined accurately according to the E-DPDCH gain factor, the wasteof transmit power of E-DPDCH is reduced, and therefore the systemcapacity is improved.

BRIEF DESCRIPTION OF THE DRAWINGS

To describe the technical solution under the present invention moreclearly, the following describes the accompanying drawings involved inthe embodiments of the present invention. Apparently, the accompanyingdrawings outlined below are not exhaustive and shall not constitute anylimitation to the scope of the present invention.

FIG. 1 is a flowchart of a method for determining transmit power in anembodiment of the present invention;

FIG. 2 shows a structure of an apparatus for determining transmit powerin an embodiment of the present invention; and

FIG. 3 shows a structure of another apparatus for determining transmitpower in an embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The following detailed description is provided with reference to theaccompanying drawings to provide a thorough understanding of the presentinvention. Evidently, the drawings and the detailed description aremerely representative of particular embodiments of the presentinvention, and the embodiments are illustrative in nature rather thanexhaustive, and shall not constitute any limitation to the scope of thepresent invention. All other embodiments, which can be derived by thoseskilled in the art from the embodiments given herein without anycreative efforts, fall within the scope of the present invention.

A method for determining a transmit power is provided in an embodimentof the present invention. The E-DPDCH gain factor in compressed mode isdetermined according to the number of E-DPDCH required for initialtransmission of data, and the transmit power of E-DPDCH is determinedaccording to the E-DPDCH gain factor. This method determines the E-DPDCHgain factor in compressed mode accurately. Because the transmit power ofE-DPDCH is determined according to the E-DPDCH gain factor, the waste oftransmit power of E-DPDCH is reduced, and therefore the system capacityis improved.

FIG. 1 is a flowchart of a method for determining a transmit power in anembodiment of the present invention. The method includes the followingsteps:

Step 101: Determine the E-DPDCH gain factor in compressed mode accordingto the number of E-DPDCH required for initial transmission of data.

In this embodiment, when a TTI is 10 ms, the E-DPDCH gain factor incompressed mode is calculated according to the number of E-DPDCHrequired for initial transmission of data, and interpolation formulas(2) and (3) are put forward.

Assuming L_(e,I,i) denotes the number of E-DPDCH required for initialtransmission of data, β_(ed,C,i) denotes the E-DPDCH gain factor, andthe current frame is a compressed frame,

$\beta_{{ed},C,i} = {\beta_{c,C,j} \cdot \sqrt{\frac{L_{e,{ref},1}}{L_{e,I,i}}} \cdot \sqrt{\left( {{\left( \frac{{\frac{L_{e,{ref},2}}{L_{e,{ref},1}}A_{{ed},{ref},2}^{2}} - A_{{ed},{ref},1}^{2}}{K_{e,{ref},2} - K_{e,{ref},1}} \right)\left( {K_{e,i} - K_{e,{ref},1}} \right)} + A_{{ed},{ref},1}^{2}} \right)} \cdot 10^{(\frac{\Delta \; {harq}}{20})} \cdot \sqrt{\frac{15 \cdot N_{{pilot},C}}{N_{{slots},I} \cdot N_{{pilot},N}}}}$

(2)

Assuming L_(e,I,i) denotes the number of E-DPDCH required for initialtransmission of data, β_(ed,R,i) denotes the E-DPDCH gain factor, andthe current frame is a non-compressed frame,

$\begin{matrix}{\beta_{{ed},R,i} = {{\sqrt{\frac{L_{e,{ref},1}}{L_{e,I,i}}} \cdot \sqrt{\left( {{\left( \frac{{\frac{L_{e,{ref},2}}{L_{e,{ref},1}}\beta_{{ed},{ref},2}^{2}} - \beta_{{ed},{ref},1}^{2}}{K_{e,{ref},2} - K_{e,{ref},1}} \right)\left( {K_{e,i} - K_{e,{ref},1}} \right)} + \beta_{{ed},{ref},1}^{2}} \right)}}{\sqrt{\frac{15}{N_{{slots},I}}} \cdot 10^{(\frac{\Delta_{harq}}{20})}}}} & (3)\end{matrix}$

In formula (2) and formula (3), β_(c,C,j) denotes a Dedicated PhysicalControl Channel (DPCCH) gain factor used for a j:th Transport FormatCombination (TFC) in compressed mode;

${A_{{ed},{ref},1} = \frac{\beta_{{ed},{ref},1}}{\beta_{c}}},{A_{{ed},{ref},2} = \frac{\beta_{{ed},{ref},2}}{\beta_{c}}},$

and β_(c) is a DPCCH gain factor in non-compressed mode; β_(ed,ref,1)and β_(ed,ref,2) denote the E-DPDCH gain factors of the first and secondreference E-TFCs respectively; L_(e,ref,1) and L_(e,ref,2) denote thenumber of E-DPDCHs used for the first and second reference E-TFCsrespectively; if the spreading factor of E-DPDCH is 2, L_(e,ref,1) andL_(e,ref,2) denote the number of channels assuming the spreading factorof E-DPDCH is 4; K_(e,ref,1) and K_(e,ref,2) denote the transport blocksizes of the first and second reference E-TFCs respectively; K_(e,i)denotes the transport block size of the i:th E-TFC; Δ_(harq) denotes theoffset of the HARQ, and is specified by the upper layer; N_(pilot,C) isthe number of pilot bits per slot on the DPCCH in compressed frame;N_(pilot,N) is the number of pilot bits per slot on the DPCCH innon-compressed frame; N_(slots,I) is the number of non DiscontinuousTransmission (DTX) slots in a frame used for initial transmission ofdata.

Step 102: Determine transmit power of E-DPDCH according to the E-DPDCHgain factor in compressed mode.

One of the methods for determining the transmit power of the E-DPDCH is:obtain a power offset according to the ratio of the E-DPDCH gain factorto the DPCCH gain factor, and then obtain the transmit power of E-DPDCHaccording to the power offset and absolute power of the DPCCH.

In the method for determining the transmit power in the foregoingembodiment, the E-DPDCH gain factor in compressed mode is determinedaccording to the number of E-DPDCH required for initial transmission ofdata, and therefore, the E-DPDCH gain factor in compressed mode isdetermined accurately, the transmit power of E-DPDCH is determinedaccording to the E-DPDCH gain factor, the waste of transmit power ofE-DPDCH is reduced, and therefore the system capacity is improved.

As shown in FIG. 2, an apparatus for determining transmit power in anembodiment of the present invention includes:

a gain factor determining module 21, configured to determine the E-DPDCHgain factor in compressed mode according to the number of E-DPDCHrequired for initial transmission of data; and

a power determining module 22, configured to determine the transmitpower of E-DPDCH according to the E-DPDCH gain factor determined by theE-DPDCH gain factor determining module 21.

As shown in FIG. 3, the gain factor determining module 21 may include afirst determining submodule 211 and a second determining submodule 212.

The first determining submodule 211 is configured to determine theE-DPDCH gain factor when L_(e,I,i) denotes the number of E-DPDCHrequired for initial transmission of data, β_(ed,C,i) denotes theE-DPDCH gain factor, and the current frame is a compressed frame:

$\beta_{{ed},C,i} = {\beta_{c,C,j} \cdot \sqrt{\frac{L_{e,{ref},1}}{L_{e,I,i}}} \cdot \sqrt{\left( {{\left( \frac{{\frac{L_{e,{ref},2}}{L_{e,{ref},1}}A_{{ed},{ref},2}^{2}} - A_{{ed},{ref},1}^{2}}{K_{e,{ref},2} - K_{e,{ref},1}} \right)\left( {K_{e,i} - K_{e,{ref},1}} \right)} + A_{{ed},{ref},1}^{2}} \right)} \cdot 10^{(\frac{\Delta \; {harq}}{20})} \cdot \sqrt{\frac{15 \cdot N_{{pilot},C}}{N_{{slots},I} \cdot N_{{pilot},N}}}}$

The second determining submodule 212 is configured to determine theE-DPDCH gain factor when L_(e,I,i) denotes the number of E-DPDCHrequired for initial transmission of data, β_(ed,R,i) denotes theE-DPDCH gain factor, and the current frame is a non-compressed frame:

$\beta_{{ed},R,i} = {{\sqrt{\frac{L_{e,{ref},1}}{L_{e,I,i}}} \cdot \sqrt{\left( {{\left( \frac{{\frac{L_{e,{ref},2}}{L_{e,{ref},1}}\beta_{{ed},{ref},2}^{2}} - \beta_{{ed},{ref},1}^{2}}{K_{e,{ref},2} - K_{e,{ref},1}} \right)\left( {K_{e,i} - K_{e,{ref},1}} \right)} + \beta_{{ed},{ref},1}^{2}} \right)}}{\sqrt{\frac{15}{N_{{slots},I}}} \cdot 10^{(\frac{\Delta_{harq}}{20})}}}$

In the formula above, β_(c,C,j) denotes the DPCCH gain factor used forthe j:th TFC in compressed mode;

${A_{{ed},{ref},1} = \frac{\beta_{{ed},{ref},1}}{\beta_{c}}},{A_{{ed},{ref},2} = \frac{\beta_{{ed},{ref},2}}{\beta_{c}}},$

and β_(c) is the DPCCH gain factor in non-compressed mode; β_(e,ref,1)and β_(e,ref,2) denote the E-DPDCH gain factors of the first and secondreference E-TFCs; L_(e,ref,1) and L_(e,ref,2) denote the number ofE-DPDCHs used for the first and second reference E-TFCs; K_(e,ref,1) andK_(e,ref,2) denote the transport block sizes of the first and secondreference E-TFCs; K_(e,i) denotes the transport block size of the i:thE-TFC; Δ_(harq) denotes the offset of the HARQ; N_(pilot,C) is thenumber of pilot bits per slot on of the DPCCH in compressed frame;N_(pilot,N) is the number of pilot bits per slot of the DPCCH innon-compressed frame; and N_(slots,I) is the number of non DTX slots ina frame used for initial transmission of data.

In the apparatus for determining the transmit power in the foregoingembodiment, the gain factor determining module 21 determines the E-DPDCHgain factor in compressed mode according to the number of E-DPDCHrequired for initial transmission of data. Therefore, the E-DPDCH gainfactor in compressed mode is determined accurately, the powerdetermining module 22 determines the transmit power of E-DPDCH accordingto the E-DPDCH gain factor, the waste of transmit power of E-DPDCH isreduced, and therefore the system capacity is improved.

Further, a base station is provided in an embodiment of the presentinvention, and the base station includes the foregoing apparatus fordetermining transmission power. The base station may include all or partof the modules of the foregoing apparatus for determining the transmitpower.

Further, a terminal is provided in an embodiment of the presentinvention, and the terminal includes the foregoing apparatus fordetermining a transmit power. The terminal may include all or part ofthe modules of the foregoing apparatus for determining a transmit power.

After reading the foregoing embodiments, those skilled in the art areclearly aware that the present invention may be implemented throughhardware, or through software in addition to a necessary universalhardware platform. Based on such understanding, the technical solutionunder the present invention may be embodied in a software product. Thesoftware product may be stored in a nonvolatile storage medium (such asa Compact Disk-Read Only Memory (CD-ROM), a Universal Serial Bus (USB)disk, or a mobile hard disk), and may include several instructions thatenable a computer device (such as a personal computer, a server, or anetwork device) to perform the method according to any embodiment of thepresent invention.

It is understandable to those skilled in the art that the accompanyingdrawings are only schematic diagrams of the exemplary embodiments, andthe modules or processes in the accompanying drawings are not mandatoryfor implementing the present invention.

It is understandable to those skilled in the art that the modules in anapparatus provided in an embodiment of the present invention may bedistributed in the apparatus described herein, or may be located in oneor more apparatuses different from the apparatus described herein. Themodules may be combined into one module, or split into multiplesubmodules.

The sequence number of the embodiment above is designed to facilitatedescription only, and does not represent the order of preference.

Detailed above are several exemplary embodiments of the presentinvention, and the scope of the present invention is not limitedthereto. Any modifications or variations that can be derived by thoseskilled in the art shall fall within the scope of the present invention.

1. A computer readable medium, comprising: a computer program code comprising one or more instructions, which, when executed by a computer device, cause the computer device to determine an Enhanced Dedicated Channel Dedicated Physical Data Channel (E-DPDCH) gain factor in compressed mode, according to the number of E-DPDCHs for an initial transmission of data, wherein, when a current frame is a compressed frame, the computer program code is configured to, when executed by the computer device, cause the computer device to determine the E-DPDCH gain factor in the compressed mode as follows: $\beta_{{ed},C,i} = {\beta_{c,C,j} \cdot \sqrt{\frac{L_{e,{ref},1}}{L_{e,I,i}}} \cdot \sqrt{\left( {{\left( \frac{{\frac{L_{e,{ref},2}}{L_{e,{ref},1}}A_{{ed},{ref},2}^{2}} - A_{{ed},{ref},1}^{2}}{K_{e,{ref},2} - K_{e,{ref},1}} \right)\left( {K_{e,i} - K_{e,{ref},1}} \right)} + A_{{ed},{ref},1}^{2}} \right)} \cdot 10^{(\frac{\Delta \; {harq}}{20})} \cdot \sqrt{\frac{15 \cdot N_{{pilot},C}}{N_{{slots},I} \cdot N_{{pilot},N}}}}$ wherein, β_(ed,C,i) denotes the E-DPDCH gain factor in the compressed mode, L_(e,I,i) denotes the number of the E-DPDCHs for the initial transmission of data, β_(c,C,j) denotes a Dedicated Physical Control Channel (DPCCH) gain factor used for the j:th TFC in the compressed mode, ${A_{{ed},{ref},1} = \frac{\beta_{{ed},{ref},1}}{\beta_{c}}},$ and ${A_{{ed},{ref},2} = \frac{\beta_{{ed},{ref},2}}{\beta_{c}}},$ where β_(c) is a DPCCH gain factor in non-compressed mode, β_(ed,ref,1) and β_(ed,ref,2) denote the E-DPDCH gain factors of a first and a second reference E-TFCs, respectively, L_(e,ref,1) and L_(e,ref,2) denote the number of the E-DPDCHs used for the first and second reference E-TFCs, respectively, K_(e,ref,1) and K_(e,ref,2) denote transport block sizes of the first and second reference E-TFCs, respectively, K_(e,i) denotes the transport block size of the i:th E-TFC, Δ_(harq) denotes an offset of a Hybrid Automatic Repeat Request (HARQ), N_(pilot,C) denotes the number of pilot bits per slot on a DPCCH in the compressed mode, N_(pilot,N) denotes the number of pilot bits per slot on the DPCCH in the non-compressed mode, and N_(slots,I) denotes the number of non Discontinuous Transmission (DTX) slots in a frame used for the initial transmission of data.
 2. The computer readable medium according to claim 1, wherein the computer program code, when executed by the computer device, further causes the computer device to determine a transmit power of the E-DPDCH according to the E-DPDCH gain factor in the compressed mode.
 3. The computer readable medium according to claim 2, wherein the computer program code, when executed by the computer device, causes the computer device to further determine a power offset according to a ratio of the E-DPDCH gain factor in the compressed mode to the DPCCH gain factor in the compressed mode, and determine the transmit power of the E-DPDCH according to the determined power offset and an absolute power of the DPCCH.
 4. A computer readable medium comprising: a computer program code comprising one or more instructions, which, when executed by a computer device, causes the computer device to an Enhanced Dedicated Channel Dedicated Physical Data Channel (E-DPDCH) gain factor in compressed mode according to the number of E-DPDCH for an initial transmission of data, wherein, when a current frame is a non-compressed frame, the computer program code is configured to, when executed by the computer device, cause the computer device to determine the E-DPDCH gain factor as follows: ${\beta_{{ed},R,i} = {{\sqrt{\frac{L_{e,{ref},1}}{L_{e,I,i}}} \cdot \sqrt{\left( {{\left( \frac{{\frac{L_{e,{ref},2}}{L_{e,{ref},1}}\beta_{{ed},{ref},2}^{2}} - \beta_{{ed},{ref},1}^{2}}{K_{e,{ref},2} - K_{e,{ref},1}} \right)\left( {K_{e,i} - K_{e,{ref},1}} \right)} + \beta_{{ed},{ref},1}^{2}} \right)}}{\sqrt{\frac{15}{N_{{slots},I}}} \cdot 10^{(\frac{\Delta_{harq}}{20})}}}},$ wherein, β_(ed,R,i) denotes the E-DPDCH gain factor in the compressed mode, L_(e,I,i) denotes the number of the E-DPDCHs used for the initial transmission of data, β_(e,ref,1) and β_(e,ref,2) denote E-DPDCH gain factors of first and second reference E-TFCs, respectively, L_(e,ref,1) and L_(e,ref,2) denote the number of the E-DPDCHs used for the first and second reference E-TFCs, respectively, K_(e,ref,1) and K_(e,ref,2) denote transport block sizes of the first and second reference E-TFCs, respectively, K_(e,i) denotes transport block size of the i:th E-TFC, Δ_(harq) denotes an offset of a hybrid automatic repeat request (HARQ), and N_(slots,I) denotes the number of non Discontinuous Transmission (DTX) slots in a frame used for the initial transmission of data.
 5. The computer readable medium according to claim 4, wherein the computer program code, when executed by the computer device, further causes the computer device to determine a transmit power of the E-DPDCH according to the determined E-DPDCH gain factor in the compressed mode.
 6. The computer readable medium according to claim 5, wherein the computer program code, when executed by the computer device, causes the computer device to: further determine a power offset according to a ratio of the E-DPDCH gain factor in the compressed mode to a Dedicated Physical Control Channel (DPCCH) gain factor, and determine the transmit power of the E-DPDCH according to the determined power offset and an absolute power of a DPCCH.
 7. A network apparatus comprising: a memory; and a processor configured to execute one or more instructions stored in the memory, wherein, when a current frame is a compressed frame, the instructions are configured to determine, according to the number of E-DPDCHs for an initial transmission of data, an Enhanced Dedicated Channel Dedicated Physical Data Channel (E-DPDCH) gain factor in compressed mode as follows: $\beta_{{ed},C,i} = {\beta_{c,C,j} \cdot \sqrt{\frac{L_{e,{ref},1}}{L_{e,I,i}}} \cdot \sqrt{\left( {{\left( \frac{{\frac{L_{e,{ref},2}}{L_{e,{ref},1}}A_{{ed},{ref},2}^{2}} - A_{{ed},{ref},1}^{2}}{K_{e,{ref},2} - K_{e,{ref},1}} \right)\left( {K_{e,i} - K_{e,{ref},1}} \right)} + A_{{ed},{ref},1}^{2}} \right)} \cdot 10^{(\frac{\Delta \; {harq}}{20})} \cdot \sqrt{\frac{15 \cdot N_{{pilot},C}}{N_{{slots},I} \cdot N_{{pilot},N}}}}$ wherein, β_(ed,C,i) denotes the E-DPDCH gain factor in the compressed mode, L_(e,I,i) denotes the number of the E-DPDCHs for the initial transmission of data, β_(c,C,j) denotes a Dedicated Physical Control Channel (DPCCH) gain factor used for the j:th TFC in the compressed mode, ${A_{{ed},{ref},1} = \frac{\beta_{{ed},{ref},1}}{\beta_{c}}},$ and ${A_{{ed},{ref},2} = \frac{\beta_{{ed},{ref},2}}{\beta_{c}}},$ where β_(c) is a DPCCH gain factor in non-compressed mode, β_(e,ref,1) and β_(e,ref,1) denote the E-DPDCH gain factors of a first and a second reference E-TFCs, respectively, L_(e,ref,1) and L_(e,ref,2) denote the number of the E-DPDCHs used for the first and second reference E-TFCs, respectively, K_(e,ref,1) and K_(e,ref,2) denote transport block sizes of the first and second reference E-TFCs, respectively, K_(e,i) denotes the transport block size of the i:th E-TFC, Δ^(harq) denotes an offset of a Hybrid Automatic Repeat Request (HARQ), N_(pilot,C) denotes the number of pilot bits per slot on a DPCCH in the compressed mode, N_(pilot,N) denotes the number of pilot bits per slot on the DPCCH in the non-compressed mode, and N_(slots,I) denotes the number of non Discontinuous Transmission (DTX) slots in a frame used for the initial transmission of data.
 8. The apparatus according to claim 7, wherein the instructions are further configured to determine a transmit power of the E-DPDCH according to the E-DPDCH gain factor in the compressed mode.
 9. The apparatus according to claim 8, wherein instructions are further configured to determine a power offset according to a ratio of the E-DPDCH gain factor in the compressed mode to the DPCCH gain factor in the compressed mode, and wherein the transmit power of the E-DPDCH is determined according to the determined power offset and an absolute power of the DPCCH.
 10. An apparatus comprising: a memory; and a processor configured to perform one or more instructions, wherein, when a current frame is a non-compressed frame, the instructions are configured to determine, according to the number of E-DPDCHs for an initial transmission of data, an Enhanced Dedicated Channel Dedicated Physical Data Channel (E-DPDCH) gain factor in compressed mode as follows: ${\beta_{{ed},R,i} = {{\sqrt{\frac{L_{e,{ref},1}}{L_{e,I,i}}} \cdot \sqrt{\left( {{\left( \frac{{\frac{L_{e,{ref},2}}{L_{e,{ref},1}}\beta_{{ed},{ref},2}^{2}} - \beta_{{ed},{ref},1}^{2}}{K_{e,{ref},2} - K_{e,{ref},1}} \right)\left( {K_{e,i} - K_{e,{ref},1}} \right)} + \beta_{{ed},{ref},1}^{2}} \right)}}{\sqrt{\frac{15}{N_{{slots},I}}} \cdot 10^{(\frac{\Delta_{harq}}{20})}}}},$ wherein, β_(ed,R,i) denotes the E-DPDCH gain factor in the compressed mode, L_(e,I,i) denotes the number of the E-DPDCHs used for the initial transmission of data, β_(e,ref,1) and β_(e,ref,2) denote E-DPDCH gain factors of first and second reference E-TFCs, respectively, L_(e,ref,1) and L_(e,ref,2) denote the number of the E-DPDCHs used for the first and second reference E-TFCs, respectively, K_(e,ref,1) and K_(e,ref,2) denote transport block sizes of the first and second reference E-TFCs, respectively, K_(e,i) denotes transport block size of the i:th E-TFC, Δ_(harq) denotes an offset of a hybrid automatic repeat request (HARQ), and N_(slots,I) denotes the number of non Discontinuous Transmission (DTX) slots in a frame used for the initial transmission of data.
 11. The apparatus according to claim 10, wherein the instructions are further configured to determine a transmit power of the E-DPDCH according to the determined E-DPDCH gain factor in the compressed mode.
 12. The apparatus according to claim 10, wherein the instructions are configured to further determine a power offset according to a ratio of the E-DPDCH gain factor in the compressed mode to a Dedicated Physical Control Channel (DPCCH) gain factor, wherein the transmit power of the E-DPDCH is determined according to the determined power offset and an absolute power of a DPCCH. 